Thermoplastic polyurethane is used in broad fields due to its superior elastic property, abrasion resistance and the like. For example, molded articles produced by extrusion molding such as film, sheet, tube, pipe and the like, various molded articles obtained by injection molding and the like are used for various applications in view of superior properties thereof.
Of those, polyether-based thermoplastic polyurethane is widely used for the aforementioned applications by utilizing the superior properties thereof such as hydrolysis resistance, cold resistance and the like.
As polyether-based thermoplastic polyurethane, thermoplastic polyurethane obtained by using, as a chain extender for the production of thermoplastic polyurethane, a combination of a chain extender having a different carbon atom number and a chain extender having a branch and the like is known, and the thermoplastic polyurethane is known to show good continuous productivity for a long time (see patent document 1).